In which cases the octet rule is violated:
`BeBr_(2),NH_(3),AlBr_(3),PBr_(5),CO_(3)^(2-),CO_(2),SO_(2),SF_(2),SF_(2),SF_(6)`

Explanation

To determine in which cases the octet rule is violated among the given compounds, we will analyze each compound one by one. The octet rule is violated when the central atom has either fewer than 8 valence electrons (hypovalency) or more than 8 valence electrons (hypervalency).

### Step-by-Step Solution:

1. **BeBr₂ (Beryllium Bromide)**:
- Beryllium (Be) has 2 valence electrons.
- In BeBr₂, Be forms two bonds with Br atoms, contributing 2 electrons from each Br (total of 4).
- Total valence electrons around Be = 2 (from Be) + 4 (from two Br) = 6.
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